The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 31, 2006
Filed:
May. 21, 2004
Takehiro Saruwatari, Kashiwara, JP;
Tetsuya Murakami, Nara, JP;
Kensaku Nakamura, Kashiba, JP;
Kousuke Yamanaka, Kashiwara, JP;
Masato Mizuhara, Takaishi, JP;
Atsuya Miyata, Osaka, JP;
Takehiro Saruwatari, Kashiwara, JP;
Tetsuya Murakami, Nara, JP;
Kensaku Nakamura, Kashiba, JP;
Kousuke Yamanaka, Kashiwara, JP;
Masato Mizuhara, Takaishi, JP;
Atsuya Miyata, Osaka, JP;
Koyo Seiko Co., Ltd., Osaka, JP;
Abstract
An electric power steering apparatus comprises a speed reduction mechanism for decelerating the rotation of an output shaft in an electric motor for steering assist. The speed reduction mechanism comprises a driving gear connected to the output shaft in the electric motor and a driven gear meshed with the driving gear. One of respective tooth sections in the driving gear and the driven gear includes a tooth section formed of a material having a relatively low hardness, and the other tooth section includes a tooth section formed of a material having a relatively high hardness. The profile of the tooth section formed of the material having a relatively low hardness is shifted in the direction in which the thickness at the root of the teeth of the tooth section is increased. The profile of the tooth section formed of the material having a relatively high hardness is shifted in the direction in which the thickness at the root of the teeth of the tooth section is decreased.